Hi otoy,
You have this sampling rate for lights and mesh emitter lights. I know if light is noisy add more samples. It's easy with 1-2 lights. We have a night scene with cars (each car has head lights, octane mesh emitter brake lights etc etc), street lights, house lights, and so on. Balancing all these lights using sampling rate is impossible. Setting lights all to 1 makes all lights noisy. Please crate a better automatic noise free lights.
The only problem we ever had with octane is noisy lights. It's the biggest pain where all your creativity goes down the drain. Other renderers somehow render noise free millions of lights. Just look at Pixar Coco. Million of street and house lights in the scene.
Thank you